In a conventional power switching system, the voltage is modulated by an electronic switch to generate a final output voltage with a small ripple. In one example, the electronic switch is a power semiconductor package device. Current technology requires the power semiconductor package device with a reduced size to fit in a small mounting space. For example, FIG. 1A shows a Dual Flat Non-Leaded (DFN) package device having a dimension of about 1.0 mm×0.6 mm (length L×width W). The DFN package device has a gate pad G, a source pad S and a drain pad D. The size of the gate pad G and the size of the source pad S are relatively small. A space E between the gate pad G and the source pad S is generally only about 0.35 mm. The length B of the drain pad D is about 0.5 mm. To fit into the dimension of about 1.0 mm×0.6 mm, the gate pad G and the source pad S are usually located very close to edges of the package device. A cutting process is performed to separate individual package devices from a semiconductor wafer. The cutting process may introduce size variation to the individual package devices. FIG. 1B shows a defected DFN package device resulting from a cutting offset. The gate pad G of the defected DFN package device is biased to an edge of the defected DFN package device and causes one side surface of the gate pad G exposed. The gate pad G may easily fall off. In a more severe cutting offset, part of the gate pad G may be cut off. Each pad needs to carry a certain amount of current or voltage.
The space E between the gate pad G and the source pad S needs to be larger than a predetermined value to assure safety of the device by avoiding coupling and lapping of the gate pad G and the source pad S with soldering paste during the process of mounting the DFN package device on a circuit board.